Simpson strong ties on the outside and 10" Grk's up through the subfloor from the bottom.
The other thing I think that is often overlooked on SIPS enclosed frames is the shear number of screws there are holding the frame to sill and screwed to the posts...especially the corners...
We use GRKs on the sill plates too....SIPS are screwed and glued to the sill plate and then screwed again through the sips to the posts.
Corners have additional lumber reinforcement in the SIPS that are screwed through to the post... I think the number of screws w/washers compared to the average clipped head nails holding OSB on the side of a house is pretty formidable...
If I had to ride out a tornado in a house...I'd want to do it in Timber Frame home that I built...
